Preheat toaster oven at 400 degrees F for 5 minutes. In that time wash potatoes, dry with paper towels and poke all over each one with a fork or knife.
Lay each large russet or red potatoes in foil and drizzle olive oil on the outside. (or you can wrap up to 4 petite potatoes together) Sprinkle with salt and wrap up tight.
Put shelf inside toaster oven on the bottom rungs and set potatoes on top. Cook at 400 F for 1 hour, at this time petite potatoes should be fork tender and can be enjoyed.
For medium to large red, russet, or sweet potatoes I like crispy skin so unwrap after 60 minutes and set on aluminum tray (it will drip a bit so you want to use this solid tray).
Slide that in and drizzle a bit more olive oil over each one, sprinkle with a bit of salt and continue cooking for 20-30 minutes or until middle is fork tender and skins are as browned as you'd like.
Video
Notes
Potatoes in toaster oven without foil
Pierce a medium russet and/or sweet potato with a fork, rub with olive oil, sprinkle with salt and place it in the toaster oven. Bake at 400°F for 45-50 minutes, or until the potato is tender. Note that the outsides will get quite dark this way and there may. be a bit of drippings from where you poked that may drip down to the bottom heat source